diff options
| -rw-r--r-- | include/linux/sched.h | 2 | ||||
| -rw-r--r-- | kernel/cgroup.c | 4 | ||||
| -rw-r--r-- | kernel/cpuset.c | 16 | ||||
| -rw-r--r-- | kernel/kthread.c | 2 | ||||
| -rw-r--r-- | kernel/sched/core.c | 9 | ||||
| -rw-r--r-- | kernel/workqueue.c | 10 |
6 files changed, 19 insertions, 24 deletions
diff --git a/include/linux/sched.h b/include/linux/sched.h index d35d2b6..e5c64f7 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1793,7 +1793,7 @@ extern void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, #define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */ #define PF_SPREAD_PAGE 0x01000000 /* Spread page cache over cpuset */ #define PF_SPREAD_SLAB 0x02000000 /* Spread some slab caches over cpuset */ -#define PF_THREAD_BOUND 0x04000000 /* Thread bound to specific cpu */ +#define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_allowed */ #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ #define PF_MEMPOLICY 0x10000000 /* Non-default NUMA mempolicy */ #define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */ diff --git a/kernel/cgroup.c b/kernel/cgroup.c index a32f943..3852d92 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -2224,11 +2224,11 @@ retry_find_task: tsk = tsk->group_leader; /* - * Workqueue threads may acquire PF_THREAD_BOUND and become + * Workqueue threads may acquire PF_NO_SETAFFINITY and become * trapped in a cpuset, or RT worker may be born in a cgroup * with no rt_runtime allocated. Just say no. */ - if (tsk == kthreadd_task || (tsk->flags & PF_THREAD_BOUND)) { + if (tsk == kthreadd_task || (tsk->flags & PF_NO_SETAFFINITY)) { ret = -EINVAL; rcu_read_unlock(); goto out_unlock_cgroup; diff --git a/kernel/cpuset.c b/kernel/cpuset.c index 4f9dfe4..f22e947 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -1388,16 +1388,16 @@ static int cpuset_can_attach(struct cgroup *cgrp, struct cgroup_taskset *tset) cgroup_taskset_for_each(task, cgrp, tset) { /* - * Kthreads bound to specific cpus cannot be moved to a new - * cpuset; we cannot change their cpu affinity and - * isolating such threads by their set of allowed nodes is - * unnecessary. Thus, cpusets are not applicable for such - * threads. This prevents checking for success of - * set_cpus_allowed_ptr() on all attached tasks before - * cpus_allowed may be changed. + * Kthreads which disallow setaffinity shouldn't be moved + * to a new cpuset; we don't want to change their cpu + * affinity and isolating such threads by their set of + * allowed nodes is unnecessary. Thus, cpusets are not + * applicable for such threads. This prevents checking for + * success of set_cpus_allowed_ptr() on all attached tasks + * before cpus_allowed may be changed. */ ret = -EINVAL; - if (task->flags & PF_THREAD_BOUND) + if (task->flags & PF_NO_SETAFFINITY) goto out_unlock; ret = security_task_setscheduler(task); if (ret) diff --git a/kernel/kthread.c b/kernel/kthread.c index 691dc2e..a2fbbb7 100644 --- a/kernel/kthread.c +++ b/kernel/kthread.c @@ -260,7 +260,7 @@ static void __kthread_bind(struct task_struct *p, unsigned int cpu) { /* It's safe because the task is inactive. */ do_set_cpus_allowed(p, cpumask_of(cpu)); - p->flags |= PF_THREAD_BOUND; + p->flags |= PF_NO_SETAFFINITY; } /** diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 7f12624a..23606ee 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -4126,6 +4126,10 @@ long sched_setaffinity(pid_t pid, const struct cpumask *in_mask) get_task_struct(p); rcu_read_unlock(); + if (p->flags & PF_NO_SETAFFINITY) { + retval = -EINVAL; + goto out_put_task; + } if (!alloc_cpumask_var(&cpus_allowed, GFP_KERNEL)) { retval = -ENOMEM; goto out_put_task; @@ -4773,11 +4777,6 @@ int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask) goto out; } - if (unlikely((p->flags & PF_THREAD_BOUND) && p != current)) { - ret = -EINVAL; - goto out; - } - do_set_cpus_allowed(p, new_mask); /* Can the task run on the task's current CPU? If so, we're done */ diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 969be0b..39a591f 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -1757,12 +1757,8 @@ static struct worker *create_worker(struct worker_pool *pool) set_user_nice(worker->task, pool->attrs->nice); set_cpus_allowed_ptr(worker->task, pool->attrs->cpumask); - /* - * %PF_THREAD_BOUND is used to prevent userland from meddling with - * cpumask of workqueue workers. This is an abuse. We need - * %PF_NO_SETAFFINITY. - */ - worker->task->flags |= PF_THREAD_BOUND; + /* prevent userland from meddling with cpumask of workqueue workers */ + worker->task->flags |= PF_NO_SETAFFINITY; /* * The caller is responsible for ensuring %POOL_DISASSOCIATED @@ -3876,7 +3872,7 @@ struct workqueue_struct *__alloc_workqueue_key(const char *fmt, } wq->rescuer = rescuer; - rescuer->task->flags |= PF_THREAD_BOUND; + rescuer->task->flags |= PF_NO_SETAFFINITY; wake_up_process(rescuer->task); } |
